German submarine U-681

History
Nazi Germany
Name	U-681
Ordered	25 August 1941
Builder	Howaldtswerke, Hamburg
Yard number	830
Laid down	21 October 1942
Launched	20 November 1943
Commissioned	3 February 1944
Fate	Sunk by depth charges on 11 March 1945
General characteristics
Class and type	Type VIIC submarine
Displacement	769 t (757 long tons) surfaced; 871 t (857 long tons) submerged;
Length	67.10 m (220 ft 2 in) (o/a); 50.50 m (165 ft 8 in) (pressure hull);
Beam	6.20 m (20 ft 4 in) (o/a); 4.70 m (15 ft 5 in) (pressure hull);
Height	9.60 m (31 ft 6 in)
Draught	4.74 m (15 ft 7 in)
Installed power	2,800–3,200 PS (2,100–2,400 kW; 2,800–3,200 bhp) (diesels); 750 PS (550 kW; 740 shp) (electric);
Propulsion	2 shafts; 2 × diesel engines; 2 × electric motors;
Speed	17.7 knots (32.8 km/h; 20.4 mph) surfaced; 7.6 knots (14.1 km/h; 8.7 mph) submerged;
Range	8,500 nmi (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph) surfaced; 80 nmi (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph) submerged;
Test depth	230 m (750 ft); Crush depth: 250–295 m (820–968 ft);
Complement	4 officers, 40–56 enlisted
Armament	5 × torpedo tubes (four bow, one stern); 14 × 53.3 cm (21 in) torpedoes or 26 TMA mines; 1 × 8.8 cm (3.46 in) deck gun (220 rounds); 1 × 3.7 cm (1.5 in) Flak M42 AA gun ; 2 × twin 2 cm (0.79 in) C/30 anti-aircraft guns;
Service record
Part of:	31st U-boat Flotilla; 3 February – 31 October 1944; 11th U-boat Flotilla; 1 November 1944 – 11 March 1945;
Identification codes:	M 49 036
Commanders:	Oblt.z.S.d.R. Helmut Bach; 3 February – 2 August 1944; Oblt.z.S. Werner Gebauer; 2 August 1944 – 11 March 1945;
Operations:	1 patrol:; 14 February – 10 March 1945;
Victories:	None

German submarine U-681 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 12 October 1942 at the Howaldtswerke yard at Hamburg, launched on 20 November 1943, and commissioned on 3 February 1944 under the command of Oberleutnant zur See d.R. Helmut Bach.

Attached to 31st U-boat Flotilla based at Kiel, U-681 completed her training period on 31 October 1944 and was assigned to front-line service.

Design

German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-681 had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged.^[1] She had a total length of 67.10 m (220 ft 2 in), a pressure hull length of 50.50 m (165 ft 8 in), a beam of 6.20 m (20 ft 4 in), a height of 9.60 m (31 ft 6 in), and a draught of 4.74 m (15 ft 7 in). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) for use while surfaced, two Siemens-Schuckert GU 343/38–8 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged. She had two shafts and two 1.23 m (4 ft) propellers. The boat was capable of operating at depths of up to 230 metres (750 ft).^[1]

The submarine had a maximum surface speed of 17.7 knots (32.8 km/h; 20.4 mph) and a maximum submerged speed of 7.6 knots (14.1 km/h; 8.7 mph).^[1] When submerged, the boat could operate for 80 nautical miles (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 8,500 nautical miles (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph). U-681 was fitted with five 53.3 cm (21 in) torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm (3.46 in) SK C/35 naval gun, (220 rounds), one 3.7 cm (1.5 in) Flak M42 and two twin 2 cm (0.79 in) C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.^[1]

Service history

On 10 March 1945, U-681 grounded off Scilly, damaging the pressure hull and propellers. Unable to dive, Werner Gebauer, the commander of the U-boat, headed for the Irish coast, hoping for internment by Irish authorities. However, the next morning PB4Y-1 Liberator N of VPB-103 spotted U-681 on the surface and went in for the attack. Eight depth charges further damaged the U-boat, and Gebauer ordered the crew to abandon ship. With sea cocks opened and demolition charges set, U-681 submerged followed by a massive explosion. Of the crew of 47, a British escort picked up 38 survivors.^[2]

References

^ ^a ^b ^c ^d Gröner 1991, pp. 43–46.
^ Busch & Röll 1999b, p. 323.

Bibliography

Busch, Rainer; Röll, Hans-Joachim (1999a). German U-boat commanders of World War II : a biographical dictionary. Translated by Brooks, Geoffrey. London, Annapolis, Md: Greenhill Books, Naval Institute Press. ISBN 1-55750-186-6.
Busch, Rainer; Röll, Hans-Joachim (1999b). Der U-Boot-Krieg, 1939-1945: Deutsche U-Boot-Verluste von September 1939 bis Mai 1945 [German U-boat losses from September 1939 to May 1945] (in German). Vol. IV. Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0514-2.
Gröner, Eric; Jung, Dieter; Maass, Martin (1991). German Warships 1815-1945: U-boats and Mine Warfare Vessels. Vol. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.